Pretty much start and go. Well, I get in, start, then buckle up, so I guess it's 10 seconds before it's moving.
Once in a while, if we get an ice storm, it may be wise to start and let it idle for 10 minutes, so as to soften the ice. But that's pretty rare, and I've only had to do that a handful of times over the years. In winter I'll start it and then clean any snow and ice off, if there is none then I'm off and driving.
If it's too cold for me to sit comfortably in the vehicle, then I failed to dress appropriately. One never knows if they will have to do some hiking after the vehicle breaks down. Or will be on the side of the road helping out a broken down motorist. Or simply has a change of plans and winds up outside for a bit (for something completely unrelated to automobiles--maybe your aunt calls and needs you to shovel their driveway or something).